12V to 19V DC to DC Converter to Power Laptops?

[AJ452]

I tried a search and didn't find anything so I apologize if it's already been covered.  Has anyone tried something like this: https://www.amazon.com/AweKing-Wate...=1537813450&sr=8-5&keywords=12v+19v+converter ?  The idea is to bypass an inverter and power brick and all the inefficiency and instead just convert straight from 12 to 19 volts DC which my laptops run on.

Good idea?  Bad idea?

 

[John61CT]

Only way to go AFAIC.

Just silly to invert from DC to AC just to transform back to DC.

Besides tip size and polarity, watch out for watts / amps, a huge gaming rig can't be run from a 5A converter.

 

[AJ452]

Right on. One appears to take a little under 4 amps and the other 3.5 amps, I figure the 15 amp converter gives me plenty of headroom for the future.

Or would that be wasting power when I could get away with a 10 amp converter? I guess it boils down to whether the converter only pulls what it needs to supply to the load or does it pull the full 15 amps regardless of what is connected to it? Hmmmm....

 

[Trebor English]

Converter things take what they need to produce what the load demands.  There are starting surges where a bigger device has a bigger starting surge.  There are efficiency differences.  I have a 400 watt inverter to power my 60 watt fridge.  A 2000 watt inverter might use 75 watts instead of 72 to make the necessary 60 watts.  

If you search for your computer model number plus car charger you might find something that will plug into your laptop directly.

 

[AJ452]

Thanks for that info.

I have thought about car charger options but I think it would probably be much cheaper to just grab the single converter that could then run all the 19 volt stuff, both current and future.

 

[John61CT]

Or would that be wasting power when I could get away with a 10 amp converter? I guess it boils down to whether the converter only pulls what it needs to supply to the load or does it pull the full 15 amps regardless of what is connected to it?

No oversize is fine.

Unlike inverters, more efficient when just-right sized, good strategy if only a few small AC-required appliances, buy dedicated smaller ones, just switch on when using that device.

 

[John61CT]

Note also, many "portable powerpaks" even little jumpstarters, have a 19V output for laptops as well as USB for recharging gadgets and 12V for everything else.

Recharge from 12V, keep both sides plugged in and it's a converter, battery evens out the draw, buffers the high-current peaks.

Get two, always keep one fully charged and you have a backup engine jumpstarter.

 

[becida]

I tried a search and didn't find anything so I apologize if it's already been covered.  Has anyone tried something like this: https://www.amazon.com/AweKing-Wate...=1537813450&sr=8-5&keywords=12v+19v+converter ?  The idea is to bypass an inverter and power brick and all the inefficiency and instead just convert straight from 12 to 19 volts DC which my laptops run on.

Good idea?  Bad idea?

I've been using one for some time, It just plugs into the 12v outlet. I went to Amazon & looked for a .. dc charger for my laptop, <brand name & model number, I was specific>. I still have to search a bit but it was there. I'm using it right now. I might have had to use the word "vehicle" in the search.
I had to know how many volts my laptop needed ( I got this off the AC block) and I made sure the one I ordered was the same as that for the output.

I've had a Universal before & that word well too. Converting 12vdc to 19.whatever vdc makes much more sense than using an inverter & listening to that fan...

Good luck!

 

[becida]

I went & took a look for "laptop car charger" & this came up.
https://www.amazon.com/CAR-CHARGER-...r=8-2-spons&keywords=laptop+car+charger&psc=1

Just to get you into the ballpark... don't forget your specific computer in the search.

 

[WanderingCanuck]

Would you trust just any DC converter you bought online to power a really expensive laptop? I have some trouble with that. What's the failure mode when it goes up in smoke? What's the likelihood it takes out the computer to?

 

[becida]

Would you trust just any DC converter you bought online to power a really expensive laptop?  I have some trouble with that.  What's the failure mode when it goes up in smoke?  What's the likelihood it takes out the computer to?

Well I've been going this route for some time now with no problems. I'm talking years .... Of course bad luck can strike, we all take our chances. 
That's life....

 

[John61CT]

Would you trust just any DC converter you bought online to power a really expensive laptop? I have some trouble with that. What's the failure mode when it goes up in smoke? What's the likelihood it takes out the computer to?

Well not just any.

But rarely does it need to be the one with the PC maker's sticker on it.

Electricity is electricity, sufficient watts, right voltage tip size and polarity is all you need,

not rocket science.

And no, with the battery in between, failure mode is usually, just stops charging, get another one.

But some Dell, HP, Apple and Lenovo models were designed to require a proprietary handshake.

Good reason to avoid buying those models.

 

[IGBT]

Would you trust just any DC converter you bought online to power a really expensive laptop?  I have some trouble with that.  What's the failure mode when it goes up in smoke?  What's the likelihood it takes out the computer to?

A boost converter that is running on 12V and supplying 19V is highly unlikely to have a failure mode that would damage the laptop.  At most I could see some sort of internal short which transferred the 12V to the output, at which point the laptop would just ignore the low voltage and not charge.

 

[WanderingCanuck]

Well, it's good that the stories of people's laptops going up in smoke are conspicuously absent.

I have a very nice Gigabyte Aero 15W, the first laptop I've ever purchased new at a painful-to-me price, and I'd be just a little upset if I were to fry it due to ignorance, stupidity, or excessive trust.

I understand that voltage is voltage, current is current. What's more concerning to me is the reliability and the voltage regulation capabilities.

But maybe I just need to have a bit more faith. Of course, I'll be testing it under load before it ever touches my laptop though. Not an immediate concern though. I was just tagging on here because I know this is more efficient than running it through an inverter with the supplied power brick.

 

[John61CT]

You'd be amazed at the wide latitude laptops accept just fine wrt voltage and poor power quality.

Battery handling buffering is a big part of that.